That I knew about, but was he convicted of any Felony? Although as I remember on Impeachment doesn’t that in itself preclude someone from ever seeking or holding Federal Office again?
Disqualification from holding an office of trust or profit under the United States is a penalty which the Senate may impose at its discretion.
However, membership in Congress is not an office “under the United States”, it is granted by the People, or until 1916 in the case of the Senate, by the States.